Explanation:
The given data is as follows.
mass (m) = 170 kg, Distance (s) = 9.6 m
Height (h) = 3.3 m, Force (F) = 1400 N
First, we will calculate the work performed by her as follows.
W = Fs
= 
= 13440 J
Hence, minimal work necessary to lift the refrigerator is as follows.
U = mgh
= 
= 5497.8 J
Therefore, we can conclude that he performed 5497.8 J of work.
Answer:
c)
Explanation:
As we know that resultant force is the net force that is acting on the system
As per Newton's II law we know that net force is product of mass and acceleration
so we will have

here we know
m = 80 kg
for circular motion acceleration is given as


now we have



Answer:
Explanation:
When we are driving we need a lot of attention and concentration. Also one involved in driving should be consious and courteous
Thus, whenever a person is drives, and when he is disactracted by Mobile phones it will destroy his presence of mind.
It will good if use mobile after stopping the vehicle
Thanks
A. 10 rations = 1 deca-ration.
b. 2000 mockingbirds = 2 x 10³ = 2 kilo-mockingbirds.
c. 10⁻⁵ phones = 1 micro-phones.
d. 10⁻⁹ goats = 1 nano-goats.
e. 1018 miners = 1.018 x 10³ = 1.018 kilo-miners.